IHMT transmission in real world

[freightboy]

So does the Vario and all the other CVTs that combine the HST with a mechanical transmission. They all lock the pump and motor together... That's the entire concept of this type of transmission. I really don't understand why you keep saying they're different.

You're missing the planetary gear set though. It has to have one as this is the key for this type of transmission to work at the efficiency levels they rate it to.

I am not missing the planetary gear, it is on the outside of the transmission. On the pump block of the I-HMT, there are pistons on both sides. Small pistons on the inside control the flow from side to side of the pump block, based on the position of the single swash plate. When the swash plate is in the upright position, which would be neutral on a hydrostat, the motor side no longer allows the output to turn and is hydraulically locked together, receiving direct power from the input shaft. If the Fendt isn't on the same shaft, it isn't possible to transfer power in this manner.

 

[airbiscuit]

As I see it, the benefits or the IMHD (or Vario) transmission are

• Variable speed
• Solid Lock Up
• Ability to service without having to split the tractor

I hope my next CUT has one

 

[ptsg]

I am not missing the planetary gear, it is on the outside of the transmission. On the pump block of the I-HMT, there are pistons on both sides. Small pistons on the inside control the flow from side to side of the pump block, based on the position of the single swash plate. When the swash plate is in the upright position, which would be neutral on a hydrostat, the motor side no longer allows the output to turn and is hydraulically locked together, receiving direct power from the input shaft. If the Fendt isn't on the same shaft, it isn't possible to transfer power in this manner.

Why not? Being on the same shaft, or being split but connected with gears, like Fendt and others do, will achieve the same exact thing, just a different layout all together...

 

[freightboy]

Why not? Being on the same shaft, or being split but connected with gears, like Fendt and others do, will achieve the same exact thing, just a different layout all together...

That is like saying that a hydrostatic transmission and CVT are the same because they utilize planetary gears. If you mean they both turn the wheels, then yes, they are the same. The internal working theory is very different.

 

[ptsg]

That is like saying that a hydrostatic transmission and CVT are the same because they utilize planetary gears. If you mean they both turn the wheels, then yes, they are the same. The internal working theory is very different.

Please, spend some time reading about those CVT, whether it's being used on Fendt, MF, Case, NH, JD or others. You'll learn very quickly that your iHMT is a CVT just like those. I really don't know what to tell you more. You clearly haven't bothered to learn how those CVT work.

 

[freightboy]

Please, spend some time reading about those CVT, whether it's being used on Fendt, MF, Case, NH, JD or others. You'll learn very quickly that your iHMT is a CVT just like those. I really don't know what to tell you more. You clearly haven't bothered to learn how those CVT work.

As mentioned before, I work with these every day. The planetary gears you are speaking of are not a part of the i-HMT. Yes, they all turn the wheels. Being on the same shaft is what differentiates the i-HMT from the other transmissions. Your comparison is similar to saying that diesel engines and gasoline engines are the same because both have a flywheel. While both provide power, they are different.

 

[ptsg]

As mentioned before, I work with these every day. The planetary gears you are speaking of are not a part of the i-HMT. Yes, they all turn the wheels. Being on the same shaft is what differentiates the i-HMT from the other transmissions. Your comparison is similar to saying that diesel engines and gasoline engines are the same because both have a flywheel. While both provide power, they are different.

You're thinking of the planetary gears as the ones on the final drives that some tractors have, which only shows you didn't even bothered to learn how those CVT (including iHMT) work.

The key part of combining the hydrostatic with the mechanical transmission, is a planetary gear set. It's all there in the videos and literature, it's just a matter of reading it.

Straight from Kanzaki website:

I've tried my best to hopefully make you understand how the transmissions work, I guess I wasn't successful.

To be honest, I really don't care anymore and I'll keep referring to it as a scaled down version of the Vario, because it's exactly what is. If that wasn't the case, I don't think Yanmar would have the slightest interest on putting "Vario" in their website as well, yet they do. This helps people finding more about these transmissions as there is very little info about the iHMT out there.

Have a good one.

 

[freightboy]

You're thinking of the planetary gears as the ones on the final drives that some tractors have, which only shows you didn't even bothered to learn how those CVT (including iHMT) work.

The key part of combining the hydrostatic with the mechanical transmission, is a planetary gear set. It's all there in the videos and literature, it's just a matter of reading it.

Straight from Kanzaki website:

View attachment 2391861

I've tried my best to hopefully make you understand how the transmissions work, I guess I wasn't successful.

To be honest, I really don't care anymore and I'll keep referring to it as a scaled down version of the Vario, because it's exactly what is. If that wasn't the case, I don't think Yanmar would have the slightest interest on putting "Vario" in their website as well, yet they do. This helps people finding more about these transmissions as there is very little info about the iHMT out there.

Have a good one.

It is not a scaled down version of the Vario. I have tried over and over to get you to stop spreading false information. As for your clip, it is a hydro mechanical transmission developed by Kanzaki. It is not the i-HMT, also developed by Kanzaki. Vario is a nice word, but if it used Vario and copied the transmission don't you think there would be a lawsuit? The i-HMT works on the single shaft and has a transmission ECU and draft controller (not to be confused with draft control of a 3-point hitch) that offer precise control. I am not just a technician at a shop, I work with these every day and have a pretty good idea of how they work. As stated in my previous post, the pump and motor being on the same shaft differentiates how the transmission works. They are not the same. Please stop spreading false information.

 

[ptsg]

It is not a scaled down version of the Vario. I have tried over and over to get you to stop spreading false information. As for your clip, it is a hydro mechanical transmission developed by Kanzaki. It is not the i-HMT, also developed by Kanzaki. Vario is a nice word, but if it used Vario and copied the transmission don't you think there would be a lawsuit? The i-HMT works on the single shaft and has a transmission ECU and draft controller (not to be confused with draft control of a 3-point hitch) that offer precise control. I am not just a technician at a shop, I work with these every day and have a pretty good idea of how they work. As stated in my previous post, the pump and motor being on the same shaft differentiates how the transmission works. They are not the same. Please stop spreading false information.

Accordingly to you, even Yanmar seems to be spreading false information on their own website.

Page from Kanzaki, now mentioning "iHMT", since that seems to be a big deal.

Straight from Yanmar website:

I'm sure it's all false information. It would be nice if Yanmar would do a proper video and maybe animation, explaining the i-HMT properly. That video with the guy holding the HST part of it, doesn't even come close to do a good job explaining it.

 

[hayden]

I am not missing the planetary gear, it is on the outside of the transmission. On the pump block of the I-HMT, there are pistons on both sides. Small pistons on the inside control the flow from side to side of the pump block, based on the position of the single swash plate. When the swash plate is in the upright position, which would be neutral on a hydrostat, the motor side no longer allows the output to turn and is hydraulically locked together, receiving direct power from the input shaft. If the Fendt isn't on the same shaft, it isn't possible to transfer power in this manner.

That may be true, but so what? Why does it matter? All IVTs accomplish the same thing, though the implementation details vary between products. They all hydraulically lock the pump and motor when fully engaged, and otherwise vary how much the plentary freewheels vs drives the output by loading it with the pump and assisting the drive with the motor. I think you are just describing an implementation difference. Perhaps it's cheaper to build, or more compact, or fewer moving parts, but functionally I'm not seeing any difference, and I haven't heard you describe any functional difference.